Field of the Invention
The present invention relates to a method for positioning a slice of a person being examined in a magnetic resonance examination, wherein the slice positioning can take place using automatic alignment information and manual positioning information. The invention further relates to a magnetic resonance apparatus designed to implement such a method.
Description of the Prior Art
Automatic slice positioning in an imaging examination, in particular in magnetic resonance (MR) examinations, is used to simplify the positioning of the person being examined in, for instance, a magnetic resonance system. The automatic slice positioning is also referred to as auto-align function. Once localization information has been determined, for instance with the use of a so-called localizer algorithm, corresponding information required for positioning can be determined, with the use of the automatic slice positioning, such as in the form of matrices, in order to acquire an MR data record from certain organs or regions of the person being examined. This information is stored in the system and, based on a selection by a user, the auto-align function can access this information and automatically position the slice to be measured at the suitable position with the use of the information. Manual positioning by a person operating the magnetic resonance system thus is not needed, because the apparatus itself shifts the slices to the desired position.
The operator, however, often is not entirely satisfied with the automatically determined position and adds, for instance, an additional translation or rotation thereto. The changed position is then stored in a magnetic resonance measurement protocol. If it is used again, the magnetic resonance measurement protocol thus will acquire MR data again precisely at the desired position.
The manual additional translation or rotation performed by the operator/technician usually has a similar effect on the slice positioning as the automatic slice positioning by means of the auto-align function. If, for instance, a magnetic resonance measurement protocol is used that was produced by an automatic slice positioning and an additional manual translation or rotation, the resulting slice positioning is now known. Then, if the magnetic resonance protocol is reused and an automatic slice positioning is applied again, for instance with the use of the auto-align function, the slice positioning is shifted again in accordance with the auto-align function. This, however, does not result in the desired slice positioning, because the starting point was already used by the first automatic slice positioning.